/Engine/Plugins/Animation/ControlRig/Source/ControlRigEditor/Public/ControlConstraintChannelInterface.h
Add an active/inactive key to the constraint channel if needed and does the transform compensation on the control's transform channels.
virtual bool SmartConstraintKey ( [UTickableTransformConstraint](API\Runtime\Constraints\UTickableTransformConstraint) * InConstraint, const [TOptional](API\Runtime\Core\IO\TOptional)< bool > & InOptActive, const [FFrameNumber](API\Runtime\Core\Misc\FFrameNumber) & InTime, const [TSharedPtr](API\Runtime\Core\Templates\TSharedPtr)< [ISequencer](API\Editor\Sequencer\ISequencer) > & InSequencer )